Hello all. I would like to introduce myself. My name is Steve, and I am new to the forum. IÔÇÖve been reading a bit here for a couple weeks and I am very impressed with all the help that is available here from the masters.
I am in the construction trades, cabinetmaking specifically. I really enjoy doing stuff myself and IÔÇÖll attempt anything, and itÔÇÖs good there are message boards where do-it-yourselfers can learn. IÔÇÖve completed many first-time projects just by studying message board content.
A couple years ago my wife and I moved from Austin to the country near Bastrop, built a new cabinet shop, an Aquaponics system in a large greenhouse, and we entertain the idea of living off-grid. (IÔÇÖm not thinking of powering the cabinet shop equipment from batteries, donÔÇÖt worry.) We would, however, like to be able to at least provide backup power in case of some sort of grid failure. In the summertime, the Aquaponics grow beds would get pretty dry without continuous water flow from the fish tank.
When we had the shop built, I wired the electrical, including 3 phase. That kind of stuff is pretty straightforward, but DC electrical seems to be a bit different and my wife loves me, so IÔÇÖm going to be seeking help.
HereÔÇÖs what we have so far:
18 Kyocera KC175-GT modules, already mounted in a 3 high X 6 wide array
2 Outback VFX3648 inverters
2 Outback MX60 charge controllers
Outback Mate with a bunch of comms cables
Four SunXtender 258ah 12v batteries
HereÔÇÖs what I think we still need/want:
MC3 extension cables
Midnite Solar combiner box (Need to know if 15a breakers are sufficient. One breaker per string of three 24v panels.)
Midnite Solar surge protector (300v or 600v) For combiner box.
DC disconnect after combiner box if needed (need to know what size)
Three 8ÔÇØ or longer battery cables (to connect four batteries in series) (Need to know what size.)
Two longer battery cables (batteries to DC side of inverter. (Need to know what size. Length of each to be determined later.)
Two Outback Flexware 500 inverter enclosures and DC and AC breakers (Need to know which breakers and what size.)
Outback inverter output bypass (single or dual)
Outback Flexware shunts
Flexware surge protector SP-ACA (?) Other Outback Flexware prebuilt systems use them.
Outback Hub 10
Outback battery temperature probe
Outback Flexware 500 mounting plate
Outback Flexnet DC
Vented battery box (IÔÇÖll build it)
As you can tell by now, I like the Outback Flexware 500 system, so I thought I'd build one if I can find all the components.
I like the idea of a 10 circuit critical loads transfer switch, but there could very well be better ideas.
We do have a Honda 2000w inverter/generator. I don't know yet if it's big enough to top off the battery bank when needed. May have to upgrade.
The array is 170 feet away from the equipment/battery location. Based on some perhaps not-so-good advice, IÔÇÖve already run 10 gauge conductors. I get the feeling IÔÇÖm gonna need to pull larger wires and thatÔÇÖs one thing I need help with.
I think I should connect three modules in series. I could have up to 6 strings feeding into the combiner box. I think I should connect my four 12v batteries in series to make 48v. Using the string sizing tool application, it appears I only need five strings to feed one MX60. (I do have two MX60s though)
I think we have more than enough array to charge the battery bank, although we do have trees. The array does receive full sun, but there are times when part or all is shaded. IÔÇÖll just have to deal with it.
HereÔÇÖs what we want to have backup power for:
Aquaponics system fish tank water pump (100 watts 24 hours per day)
Rainwater collection system UV filter (46 watts 24 hours per day)
Rainwater collection system water pump (1100 watts maybe 1 hour per day total)
Other less critical but worthy loads if possible:
Refrigerator (nameplate says 7amps)
Freezer (nameplate says 5amps)
Satellite modem and wireless router
DC loads like ham radio
Laptop chargers
LED living area lighting
At some point we want to replace this small battery bank with a larger one and then provide for running more stuff. Possibly even adding in that second VFX3648 to make 240v and run a minisplit AC.
All told, according to my EnviroR Energy Monitor, on a very conservative day of running the entire household and greenhouse loads, and not running any large consumers, (AC, shop equipment and lighting, washing machine), we can get by on 12 kwh in 24 hours. At any one time we use around 3300 watts for our entire little house, running pretty typical maximum loads including washer/dryer (except air conditioning). When we upgrade to a larger battery bank, thatÔÇÖs what weÔÇÖll be shooting for if not more.
What I need is some help with wire sizes, AC and DC breaker sizes, component choices, anything else that I can't think of to ask. I've tried to do the math many times before, even using online solar calculators, but I think maybe God made me without a watts and amps lobe.
What have I left out? I apologize for being long winded. Cabinetmakers can be a bit anal about details.
Any and all help would be appreciated. If my request is inappropriate, please excuse my ignorance. In that case I would be interested in hiring one of you knowledgeable people for your help.
Thanks all, Steve.
